25-11-2012, 11:01 PM
1. VERNIER CALLIPER
Q.1: What is vernier calipers?
Ans. It is simple instrument by which length of an object can be measured accurately up to one-tenth
of a millimeter or one-hundredth of a centimeter.
Q.2: What is the use of Vernier Scale?
Ans. To increase the accuracy of the main scale.
Q.3: What is least count (L.C.)?
Ans. The minimum measurement that can be taken by an instrument.
Q.4: What is the least count of?
(a) meter scale (b) Stop Watch © Vernier Calliper
Ans. The least count of:
(a) meter scale = 0.1 cm or 1 mm.
(b) stop watch = 0.01 sec or 1/100 sec. or according to stop watch.
© vernier scale = 0.01 cm or 0.1 mm
Q.5: What are units of vernier scale?
Ans. Vernier has not units of its own.
Q.6: What is the difference in the measurement of one smaller division on the main scale (M.S.) and
that of vernier scale (V.S.)
Ans. (1 smallest Div. on M.S.) – (1 smallest Div. on V.S) = 0.1 – 0.09 = 0.01 cm
= Least count.
Q.7: How the L.C. of a vernier is determined?
Ans. By using the relation:
L.C. = Smallest division on Main scale [[[
Total number of divisions on vernier scale
Q.8: Will the accuracy of a vernier will increase or decrease if 20 divisions are made in the same
length?
Ans. The accuracy will increase since the L.C. will decrease i.e.
Accuracy α 1 [[[[
Least count
Q.9: Which one is smaller M.S. div. or V.S. div.?
Ans. V.S. division.
Q.10: 1 division on V.S. = _____ cm.
Ans. 0.09 cm.
10 div. on V.S. = 0.9 cm
1 div. on V.S. = 0.9/10 cm = 0.09 cm
Q.11: What are the functions of
(a) Sliding strip (b) Upper jaws
Ans. (a) For measuring depth. (b) For measuring the inner diameter.
Q.12: What is meant by zero error (Z.E.)?
Ans. The error which arises when zeros of M.S. and V.S. do not coincide upon joining the two jaws.
Q.13: When Z.E. is positive?
Ans. The Z.E. is positive when the zero of V.S. is to the right of the zero of M.S.
Q.14: How we find the corrected reading?
Ans. Corrected reading = Meaning reading – ( + Z.E.)
Q.15: Do you know any use of vernier scale?
Ans. It is used in spectrometer, barometer, traveling microscope, etc.
Q.16: What are significant figures?
Ans. Numbers 0, 1, 2, 3, ……. are called significant figures when they occur. The zero is not a
significant figure if it is at the extreme left or extreme right of a number, e.g.
1.02 has three significant figures, but 1.20 has two significant figures.
Q.17: What is meant by degree of accuracy?
Ans. It is the measurement estimated by the number of significant figures in the result.
Q.18: Why is the vernier calipers so called?
Ans. A French mathematician named Pierre Vernier invented it and it is named after him.
Q.19: How does temperature affect the length of a cylinder?
Ans. The length of a cylinder increases with the increase of temperature and decreases with the
decrease of temperature.
Q.20: What is the unit of volume?
Ans. In MKS system, the unit of volume is m
3
In CGS system, the unit of volume is cm .
3
In FPS .
system, the unit of volume is ft
3
.